CVE-2025-34146 json
nyariv sandboxjs 0.8.23 Prototype Pollution Sandbox Escape DoS
published last yr. modified last mo. also EUVD-2025-23278 , GHSA-9qm3-6qrr-c76m
- cvss
- 7.0
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 15%
- public exploits
- 0
- none known
Summary
A prototype pollution vulnerability exists in @nyariv/sandboxjs versions <= 0.8.23, allowing attackers to inject arbitrary properties into Object.prototype via crafted JavaScript code. This can result in a denial-of-service (DoS) condition or, under certain conditions, escape the sandboxed environment intended to restrict code execution. The vulnerability stems from insufficient prototype access checks in the sandbox’s executor logic, particularly in the handling of JavaScript function objects returned.
Patch / fix
- npm @nyariv/sandboxjs 0.8.24
- nyariv sandboxjs 0.8.24
Is CVE-2025-34146 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- last yr.
Exploit prediction
0.25% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- gist.github.com https://gist.github.com/Hagrid29/9df27829a491080f923c4f6b8518d7e3 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 7.0 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 4.0 | 7.0 | CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| npm | @nyariv/sandboxjs | <0.8.24 |
0.8.24 |
Affected products
- nyariv sandboxjs
Classification
- Weakness
-
- CWE-1321 Improperly Controlled Modification of Object Prototype Attributes
References
-
gist.github.com
/Hagrid29/9df27829a491080f923c4f6b8518d7e3
issue-tracking, exploit, web
-
github.com
/nyariv/SandboxJS/issues/31
issue-tracking, web
-
npmjs.com
/package/@nyariv/sandboxjs
product, web
-
vulncheck.com
/advisories/nyariv-sandboxjs-prototype-pollution-sandbox-escape-dos
third-party-advisory, web
-
nvd.nist.gov
/vuln/detail/CVE-2025-34146
advisory
-
github.com
/nyariv/SandboxJS
package
Sources
- CVE List CVE-2025-34146
- GitHub Advisory GHSA-9qm3-6qrr-c76m
- NVD CVE-2025-34146
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.